NEW YORK, Feb 6 (Reuters) - U.S. stocks drifted lower on Wednesday as investors pulled back after the recent push to five-year highs on the S&P 500 and as worries about political problems in Europe weighed on sentiment.

Transportation stocks were among the worst performers, pressured by a 9.7 percent drop in CH Robinson Worldwide to $60.48 after the freight transport company posted a lower-than-expected adjusted quarterly profit.

The benchmark S&P 500 index has advanced 6 percent this year and reached to its highest since December 2007. The Dow industrials have risen above 14,000 recently, making it a challenge for investors to push stocks higher in the absence of strong positive catalysts.

“The market is starting to feel a little tired, though we’re holding together. I think a lot of people are wondering whether this (up trend) continues,” said Frank Lesh, a futures analyst and broker at FuturePath Trading LLC in Chicago.

Also, investors have been speculating about leadership changes in Spain and Italy, as well as watching for comments from European leaders. European Central Bank policymakers are due to meet Thursday.

The Dow Jones industrial average was down 27.37 points, or 0.20 percent, at 13,951.93. The Standard & Poor’s 500 Index was down 3.66 points, or 0.24 percent, at 1,507.63. The Nasdaq Composite Index was down 12.27 points, or 0.39 percent, at 3,159.31.

Both the S&P 500 and Nasdaq rose more than 1 percent on Tuesday.

The Dow Jones Transportation average was down 0.4 percent after hitting another record high on Tuesday. The average is up 10.4 percent for the year so far and has made a series of new highs since mid-January.

Walt Disney Co was up 0.7 percent at $54.66, after the company beat estimates for quarterly adjusted earnings and gave an optimistic outlook for the next few quarters.

According to Thomson Reuters data, of 301 companies in the S&P 500 that have reported earnings, 68.1 percent have exceeded analysts’ expectations, above a 62 percent average since 1994 and 65 percent over the past four quarters. In terms of revenue, 65.8 percent of companies have topped forecasts.

Fourth-quarter earnings for S&P 500 companies are estimated to have risen 4.7 percent, according to the data, above a 1.9 percent forecast at the start of the earnings season.